SHANGHAI — A Shanghai subway train rear-ended another Tuesday, injuring more than 270 people in the latest trouble for the rapidly expanded transportation system in China's commercial center.

The crash on line 10, one of the city's newest subways, occurred after Shanghai Shentong Metro Group blogged that the line was having delays due to equipment problems.

The Shanghai Shentong Metro Group said on the Weibo microblogging site that one of its trains suffered equipment failure at 2:10 p.m. local time (2:10 a.m. ET), which then led station officers to manually direct approaching trains.

Yu Guangyao, chairman of Shanghai Metro, told The Associated Press that Tuesday's accident also was linked to problems with signaling equipment.

The collision occurred near the Yu Yuan station in central Shanghai at 2:51 p.m., according to Shanghai Metro's statements on Weibo.

271 people were hurt, none seriously, said Xu Jiangguang, head of the city's health bureau. Some of the injured were carried away on stretchers, however, and 30 were being kept overnight for observation.

Most of the injuries were bruises and bone fractures, according to the official Xinhua news agency.

Shanghai, a city of 23 million, has rapidly expanded its subway system in recent years and some lines have seen problems with faulty signaling, windows shattering, doors not opening properly and poorly trained train operators.

'Blood everywhere'
Photos posted online by passengers showed some of the injured covered in blood and lying on the floor of the train.

Shen Jun, 23, who was in the first coach of the train that collided, said "blood was everywhere."

"Many people were hurt. Look at the blood on me, on my arm," pointing at patches of blood on his shirt.

The accident snarled traffic downtown as police set up road blocks to clear the way for ambulances, and hundreds of gawkers gathered to watch as passengers were escorted out of the subway.

Firefighters helped evacuate the approximately 500 passengers on the trains, taking them out through emergency exits and walking them through the subway tunnel.

The crash, coming after a collision between two bullet trains in July in eastern China in which 40 people were killed, quickly became the most talked about topic on the wildly popular Twitter-like Sina Weibo service.

"Another accident -- what a joke. So much money has been spent, all they've built is crap," wrote "ggirl".

Some expressed doubt the inevitable probe into the crash would uncover much.

"The relevant department has already set up an investigation team -- what is this mysterious department?" wondered "money bag web."

China's cosmopolitan business hub is in the midst of an ambitious subway expansion plan. Shanghai now has 11 lines running on more than 400 km of track, as well as a magnetic levitation, or maglev, link to its main international airport.

"The alarm bells are ringing again, telling us that in economic development we cannot ignore safety and must not blindly try to follow developed Western countries. We must go one step at a time," wrote "ordinary interesting person."

High-tech safeguards were promised in 2005Shanghai had boasted that collisions could not happen on its subway, saying in 2005 after a similar incident in Thailand that it had high-tech safeguards in place.

"Today is the darkest day in the history of the Shanghai Metro's operation," said a news report by Chinese internet company Sina, citing the subway operator's official microblog about Tuesday's accident.

"No matter the ultimate cause and responsibility, (we feel) particularly guilty about the harm and losses borne by the public. We will put in our utmost ability to rescue the wounded, resume operations as soon as possible ... and cooperate with the relevant departments in the investigation."

"Even if our apologies pale in comparison to the actual injuries, we are deeply sorry."

However, the statement on Weibo was later removed. It was unclear why.

The accident in July involving the bullet trains triggered public fury at the government's perceived slow response and accusations of a cover-up, expressed via microblogging sites.

It also raised question marks over technology promoted as a symbol of the nation's growing prowess.

China said it would suspend new railway project approvals and launch safety checks on existing equipment to address public concern following that crash.

The respected Chinese magazine Caixin reported on its website that the signals used on the Shanghai subway were made by China Railway Signal & Communication Corp. -- the same company that was blamed for the faulty signals in the July crash.

Calls by Reuters to the company went unanswered on Tuesday evening.

The high-speed train crash in July reverberated into China's stock market.

Sources said in August a $5 billion listing plan by the operator of China's new Beijing-Shanghai bullet train, initially targeted for next year, will be further delayed following July's train crash.

China Railway Group, the country's largest railroad builder, said earlier this month it had dropped a plan to raise about 6.2 billion yuan via a share placement due to uncertainty over regulatory approval.